Step 2: Load kernel.bin into RAM

Note the number of bytes read, you'll need to convert this to hexidecimal for use later.

Step 3: Erase the kernel pages

Use nand erase to erase the kernel pages

LF1000 # nand erase 200000 200000

You may use nand dump 200000 to verify that the kernel pages are now all 0xFF.

Step 4: Write kernel

Use nand write to write your new kernel to flash.

LF1000 # nand write 1400000 200000 [value you wrote down in step 2]

You should use nand dump 200000 to verify that kernel was written.

Step 5: Repeat the above steps for RFS0

Use erootfs.jffs2 as the source file, 0x400000 as the target address, and 0xe00000 as the erase size.
Just like with the kernel, you will want to note the size of the binary, and only write the necessary bytes.

Step 6: Cross fingers, reboot

At this point you should be ready to boot using your new kernel and RFS. Type reset in u-boot, select normal boot and see what happens.
You should be able to use leapfrog connect to restore the remaining data.